Ganoderma lucidum (Ling Zhi or Reishi), a medicinal fungus and
mushroom, has long been used in traditional Chinese medicine
(TCM) and in Asia for promotion of health and longevity as well as
for the treatment of various diseases (1). Ganoderma lucidum has been
reported to contain immunomodulating and antitumor agents (1–3). For
example, it has been shown that G.lucidum inhibits cell proliferation,
induces apoptosis or growth arrest and suppresses cell migration of
various cancer cells (4–6). Ganoderma lucidum also inhibits tumorigenesis
and metastasis of human hepatoma cells in both cell and animal
models (7); however, the detailed mechanisms by which there is
inhibition of tumor proliferation are not well understood.
Ling Zhi-8 (LZ-8), an immunomodulatory protein, was isolated
from the mycelia of G.lucidum (8) and a complementary DNA and
a gene encoded for LZ-8 were cloned (9). This protein is regarded as